In modern office buildings, networking is predominant and internet has been actively used. Inevitably, electronic instruments such as personal computers and the like are used in numbers. High frequency noise is generated not only from these electronic instruments but also from other equipment generally referred to as electronics. Since this high-frequency noise causes various types of damage to the above-mentioned precision electronic devices, countermeasures have been recently taken such as attaching a shield against radiation noise of the electronic device itself and installing a noise cut transformer against a conduction noise. In general, connection to a grounding cable of a grounding electrode having a low impedance to a high-frequency wave, from among the grounding electrodes set in office buildings at the time of construction, is considered to be sufficient for the removal of high-frequency noise.
This high-frequency noise does not disappear into the earth through a grounding cable, but in fact remains in the grounding cable as a standing wave of a high-frequency noise having various frequencies and greater amplitude than the initial amplitude, due to repeat reflection between the grounding electrode side and the electronic instrument side of the grounding cable.
A high-frequency noise remaining on a grounding cable as such standing wave flows into electronic devices to cause malfunction of or damage to the devices, thereby causing serious problems in offices.
The present invention provides a method for easily reducing or eliminating a standing wave generated on a grounding cable by modifying the grounding cable such that a high-frequency noise does not remain as a standing wave on the grounding cable, and a cable constitution therefor.